Paul Johnson

Last seen: 7 meses ago

41 total contributions since 2020

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Problem

Find the point of intersection of tangents.
Given two points on a conic, find the point of intersection of the corresponding tangents. The conic is given in Cartesian co...

8 meses ago | 0 | 3 solvers

Problem

Find the shortest distance between a point and a straight line.
Given the Cartesian coordinates of three points A, B and C (in a flat Euclidean space), find the shortest distance between the ...

9 meses ago | 1 | 7 solvers

Solved

Kepler's Equation
Solve <http://en.wikipedia.org/wiki/Kepler's_equation Kepler's Equation>. Note that the solution is rounded down to 5 decima...

9 meses ago

Solved

Calculate the height of an object dropped from the sky
Assume that an object is dropped from 1000 meters above the surface of the earth at time t=0. The object is dropped such that t...

9 meses ago

Question

Problem editing a draft Cody problem.
Hello, I have saved some draft Cody problems, but I am unable to edit these drafts. A message appears to the effect that "some...

9 meses ago | 0 answers | 0

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answers

Solved

Find the numeric mean of the prime numbers in a matrix.
There will always be at least one prime in the matrix. Example: Input in = [ 8 3 5 9 ] Output out is 4...

9 meses ago

Solved

Indexed Probability Table
This question was inspired by a Stack Overflow question forwarded to me by Matt Simoneau. Given a vector x, make an indexed pro...

9 meses ago

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Project Euler: Problem 1, Multiples of 3 and 5
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23...

9 meses ago

Solved

Bullseye Matrix
Given n (always odd), return output a that has concentric rings of the numbers 1 through (n+1)/2 around the center point. Exampl...

9 meses ago

Solved

Find all elements less than 0 or greater than 10 and replace them with NaN
Given an input vector x, find all elements of x less than 0 or greater than 10 and replace them with NaN. Example: Input ...

10 meses ago

Solved

Knight's Tour Checker
Given a matrix a, determine whether or not a legal <http://en.wikipedia.org/wiki/Knight's_tour knight's tour> is present. The kn...

10 meses ago

Solved

Add two numbers
Given a and b, return the sum a+b in c.

10 meses ago

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Make a checkerboard matrix
Given an integer n, make an n-by-n matrix made up of alternating ones and zeros as shown below. The a(1,1) should be 1. Examp...

10 meses ago

Solved

Who Has the Most Change?
You have a matrix for which each row is a person and the columns represent the number of quarters, nickels, dimes, and pennies t...

10 meses ago

Solved

Back and Forth Rows
Given a number n, create an n-by-n matrix in which the integers from 1 to n^2 wind back and forth along the rows as shown in the...

10 meses ago

Solved

Is my wife right?
Regardless of input, output the string 'yes'.

10 meses ago

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Pizza!
Given a circular pizza with radius _z_ and thickness _a_, return the pizza's volume. [ _z_ is first input argument.] Non-scor...

10 meses ago

Solved

Determine whether a vector is monotonically increasing
Return true if the elements of the input vector increase monotonically (i.e. each element is larger than the previous). Return f...

10 meses ago

Solved

Weighted average
Given two lists of numbers, determine the weighted average. Example [1 2 3] and [10 15 20] should result in 33.333...

10 meses ago

Solved

Swap the first and last columns
Flip the outermost columns of matrix A, so that the first column becomes the last and the last column becomes the first. All oth...

10 meses ago

Solved

Sum all integers from 1 to 2^n
Given the number x, y must be the summation of all integers from 1 to 2^x. For instance if x=2 then y must be 1+2+3+4=10.

10 meses ago

Solved

Inner product of two vectors
Find the inner product of two vectors.

10 meses ago

Solved

Get the length of a given vector
Given a vector x, the output y should equal the length of x.

10 meses ago

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Triangle Numbers
Triangle numbers are the sums of successive integers. So 6 is a triangle number because 6 = 1 + 2 + 3 which can be displa...

10 meses ago

Solved

Determine if input is odd
Given the input n, return true if n is odd or false if n is even.

10 meses ago

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Back to basics 6 - Column Vector
Covering some basic topics I haven't seen elsewhere on Cody. Given an input vector, output true or false whether it is a colu...

10 meses ago

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Sum the numbers on the main diagonal
Sum the numbers on the main diagonal of an n-by-n matrix. For input: A = [1 2 4 3 6 2 2 4 7]...

10 meses ago

Solved

Area of a circle
Find the value for area of the circle if diameter is given

10 meses ago

Solved

Vectors counting by 2
Create a vector numbers from 7 to 15 in increments of 2

10 meses ago

Solved

find the maximum element of the matrix
for e.g x = [1 2; 3 4] y = 4

10 meses ago

Paul Johnson

Last seen: 7 meses ago

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